Amazon Standard Identification Number (ASIN) is retrieved and used to create a short URL which replaces currently shown in address bar (replaceState).

Not using amzn.com to gurantee keeping internationalization.
Also supports Amazon Video and Kindle Store.
Amazon Music is not supported yet.

Updates:
- Supports selecting item variations
- Removes dynamically added parameters

Based on the idea of "Amazon URL Cleaner - replaceState for Amazon" by azu, which is not maintained anymore:
https://greasyfork.org/scripts/1162


Example:

• Before:
  https://www.amazon.com/Jellycat-Bashful-Beige-Medium-inches/dp/B00163U4LK/ref=sr_1_4?s=toys-and-games&ie=UTF8&qid=1509052928&sr=1-4&keywords=bunny
• After:
  https://www.amazon.com/dp/B00163U4LK/